Ross The 7I76E can be powered with a single 8-24V supply if you only need 2A for the logic side or separate 5V and 8-24V of the inputs and outputs then you can have a much greater amperage available.

Linuxcnc does require a learning curve to get going. I do use it on my mill and lathe using just one 7I76 for both with two configs. I also have two MPG's that I use between the two machines.

If you decide to go down that route I can give you my config files as a starting point.